Epson LQ-850 User Manual page 155

4. Close the font compartment cover.
5. After you have turned on the printer and are ready to print,
select SLOT A or B by pressing the FONT button on the SelecType
panel.
This font module selection remains valid even after the printer is
turned off, reset, or initialized.
6. You can use SelecType to select any available pitch for the fonts
in the font modules.
The Multi-Font Module
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